A gastrocnemius muscle is the most superficial muscle of the back surface of a lower leg, includes two capita of a caput mediale and a caput laterale, and has a so-called “calf” shape. The gastrocnemius muscle is a muscle that contributes to plantar flexion of an angle joint or flexion of a knee joint by its main movement, that extends an ankle and assists the flexion of a knee to move by standing on the tiptoe or the like by its movement in a daily life, and that strongly moves, for example, in a lot of motions including a running motion or a jumping motion.
Accordingly, when a person grows older and muscles (particularly, gastrocnemius muscle) is weakened, it is difficult to make daily motions and a calf may feel tight with fatigue in spite of occasional sports.
On the other hand, a conventional article of clothing includes a strong sheet piece having hard stretching characteristics with a strong securing force and extending substantially along a muscle fiber direction over a belly muscle from a target tendon of a human body and a weak sheet piece having soft stretching characteristics and being located in other parts not requiring securing, and is brought into close contact with the body surface of the human body so as to exhibit a taping function with the strong sheet piece (for example, see PTL 1).
A conventional calf supporter is known which includes a drum-like tube body having clamping textures at the upper and lower ends thereof and a lower part being tapered toward the end, in which the tube body has an X-suspenders reinforcing piece which is an insertion braided texture formed of a mixed fabric of nylon threads and polyurethane threads and which brings a calf portion of the tube body in close contact in the course direction, and in which the reinforcing piece is formed of a partial plating stitch texture in which knitting threads are cut at both ends (for example, see PTL 2).
A conventional calf supporter is also known in which a V-shaped lengthwise elongation suppressing texture is formed at the circumferential edge of a calf portion of the back surface, the calf portion is a portion surrounded with two lateral portions passing through the right and left side surfaces of a triceps surae muscle from an Achilles tendon and reaching the inside of a caput mediale and the outside of a caput laterale of a gastrocnemius muscle, and the lengthwise elongation suppressing texture is formed of a synthetic texture of cut-boss stitches and tuck stitches or floating stitches (for example, see PTL 3).